I recommend that you introduce your dog to people on a short leash or invite people to your house and let them know for the first X amount of minutes you will need to do some training exercises. If your pooch jumps up or nips them as they enter the door, make an obvious negative noise like a sharp 'AH' or a NO and remove them from the situation, just a few metres away and wait until they calm down. Reintroduce them, still attached to the leash and repeat until they associate that behaviour with being put in a 'time out' hopefully after a few attempts they will return and greet your guests or walkers with a more positive greeting!!
I agree with all the comments above, but coming from an animal rescue background, I can tell you that nipping from a large dog can go a lot farther than a lot of owners think. If you’re struggling with this on a daily basis, I would get in touch with an animal trainer or behaviourist. Best of luck!
Dogs that bite are often overly excited and don’t have any self control. I don’t want to sound condescending or anything, but are you sure your dog is getting enough exercise. It could just be that he has a lot of pent up energy and he doesn’t know where else to put it.
When your dog nips at someone, tell them not to react. If you react in any way, the dog will think it’s a game and just get more excited. Try to redirect his behaviour on something else, without necessarily rewarding the nipping behaviour (this is really tricky). But if you were able to distract him when he nips without punishing or rewarding the behaviour, that would be best!
That’s a tough one. He probably never got out of the puppy biting phase. And it’s a lot harder to get dogs out of a bad habit than to prevent it altogether...but it’s still doable! If your dog is mouthy I’d give him lots of other options such as chew toys/bones/kongs, etc., Hope it works out! Regards, Patrick.